tests/lib/libc/sys/t_mlock.c

   1 /* $NetBSD: t_mlock.c,v 1.4 2012/09/08 12:25:05 martin Exp $ */
   2
   3 /*-
   4  * Copyright (c) 2012 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Jukka Ruohonen.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31 #include <sys/cdefs.h>
  32 __RCSID("$NetBSD: t_mlock.c,v 1.4 2012/09/08 12:25:05 martin Exp $");
  33
  34 #include <sys/mman.h>
  35 #include <sys/resource.h>
  36 #include <sys/wait.h>
  37 #define _KMEMUSER
  38 #include <machine/vmparam.h>
  39
  40 #include <errno.h>
  41 #include <atf-c.h>
  42 #include <stdint.h>
  43 #include <stdio.h>
  44 #include <stdlib.h>
  45 #include <unistd.h>
  46
  47 static long page = 0;
  48
  49 ATF_TC(mlock_clip);
  50 ATF_TC_HEAD(mlock_clip, tc)
  51 {
  52         atf_tc_set_md_var(tc, "descr", "Test with mlock(2) that UVM only "
  53             "clips if the clip address is within the entry (PR kern/44788)");
  54 }
  55
  56 ATF_TC_BODY(mlock_clip, tc)
  57 {
  58         void *buf;
  59
  60         buf = malloc(page);
  61         ATF_REQUIRE(buf != NULL);
  62
  63         if (page < 1024)
  64                 atf_tc_skip("page size too small");
  65
  66         for (size_t i = page; i >= 1; i = i - 1024) {
  67                 (void)mlock(buf, page - i);
  68                 (void)munlock(buf, page - i);
  69         }
  70
  71         free(buf);
  72 }
  73
  74 ATF_TC(mlock_err);
  75 ATF_TC_HEAD(mlock_err, tc)
  76 {
  77         atf_tc_set_md_var(tc, "descr",
  78             "Test error conditions in mlock(2) and munlock(2)");
  79 }
  80
  81 ATF_TC_BODY(mlock_err, tc)
  82 {
  83         void *invalid_ptr;
  84         int null_errno = ENOMEM;        /* error expected for NULL */
  85
  86 #ifdef VM_MIN_ADDRESS
  87         if ((uintptr_t)VM_MIN_ADDRESS > 0)
  88                 null_errno = EINVAL;    /* NULL is not inside user VM */
  89 #endif
  90
  91         errno = 0;
  92         ATF_REQUIRE_ERRNO(null_errno, mlock(NULL, page) == -1);
  93
  94         errno = 0;
  95         ATF_REQUIRE_ERRNO(null_errno, mlock((char *)0, page) == -1);
  96
  97         errno = 0;
  98         ATF_REQUIRE_ERRNO(EINVAL, mlock((char *)-1, page) == -1);
  99
 100         errno = 0;
 101         ATF_REQUIRE_ERRNO(null_errno, munlock(NULL, page) == -1);
 102
 103         errno = 0;
 104         ATF_REQUIRE_ERRNO(null_errno, munlock((char *)0, page) == -1);
 105
 106         errno = 0;
 107         ATF_REQUIRE_ERRNO(EINVAL, munlock((char *)-1, page) == -1);
 108
 109         /*
 110          * Try to create a pointer to an unmapped page - first after current
 111          * brk will likely do.
 112          */
 113         invalid_ptr = (void*)(((uintptr_t)sbrk(0)+page) & ~(page-1));
 114         printf("testing with (hopefully) invalid pointer %p\n", invalid_ptr);
 115
 116         errno = 0;
 117         ATF_REQUIRE_ERRNO(ENOMEM, mlock(invalid_ptr, page) == -1);
 118
 119         errno = 0;
 120         ATF_REQUIRE_ERRNO(ENOMEM, munlock(invalid_ptr, page) == -1);
 121 }
 122
 123 ATF_TC(mlock_limits);
 124 ATF_TC_HEAD(mlock_limits, tc)
 125 {
 126         atf_tc_set_md_var(tc, "descr", "Test system limits with mlock(2)");
 127 }
 128
 129 ATF_TC_BODY(mlock_limits, tc)
 130 {
 131         struct rlimit res;
 132         void *buf;
 133         pid_t pid;
 134         int sta;
 135
 136         buf = malloc(page);
 137         ATF_REQUIRE(buf != NULL);
 138
 139         pid = fork();
 140         ATF_REQUIRE(pid >= 0);
 141
 142         if (pid == 0) {
 143
 144                 for (ssize_t i = page; i >= 2; i -= 100) {
 145
 146                         res.rlim_cur = i - 1;
 147                         res.rlim_max = i - 1;
 148
 149                         (void)fprintf(stderr, "trying to lock %zd bytes "
 150                             "with %zu byte limit\n", i, (size_t)res.rlim_cur);
 151
 152                         if (setrlimit(RLIMIT_MEMLOCK, &res) != 0)
 153                                 _exit(EXIT_FAILURE);
 154
 155                         errno = 0;
 156
 157                         if (mlock(buf, i) != -1 || errno != EAGAIN) {
 158                                 (void)munlock(buf, i);
 159                                 _exit(EXIT_FAILURE);
 160                         }
 161                 }
 162
 163                 _exit(EXIT_SUCCESS);
 164         }
 165
 166         (void)wait(&sta);
 167
 168         if (WIFEXITED(sta) == 0 || WEXITSTATUS(sta) != EXIT_SUCCESS)
 169                 atf_tc_fail("mlock(2) locked beyond system limits");
 170
 171         free(buf);
 172 }
 173
 174 ATF_TC(mlock_mmap);
 175 ATF_TC_HEAD(mlock_mmap, tc)
 176 {
 177         atf_tc_set_md_var(tc, "descr", "Test mlock(2)-mmap(2) interaction");
 178 }
 179
 180 ATF_TC_BODY(mlock_mmap, tc)
 181 {
 182         static const int flags = MAP_ANON | MAP_PRIVATE | MAP_WIRED;
 183         void *buf;
 184
 185         /*
 186          * Make a wired RW mapping and check that mlock(2)
 187          * does not fail for the (already locked) mapping.
 188          */
 189         buf = mmap(NULL, page, PROT_READ | PROT_WRITE, flags, -1, 0);
 190
 191         ATF_REQUIRE(buf != MAP_FAILED);
 192         ATF_REQUIRE(mlock(buf, page) == 0);
 193         ATF_REQUIRE(munlock(buf, page) == 0);
 194         ATF_REQUIRE(munmap(buf, page) == 0);
 195         ATF_REQUIRE(munlock(buf, page) != 0);
 196
 197         /*
 198          * But it should be impossible to mlock(2) a PROT_NONE mapping.
 199          */
 200         buf = mmap(NULL, page, PROT_NONE, flags, -1, 0);
 201
 202         ATF_REQUIRE(buf != MAP_FAILED);
 203         ATF_REQUIRE(mlock(buf, page) != 0);
 204         ATF_REQUIRE(munmap(buf, page) == 0);
 205 }
 206
 207 ATF_TC(mlock_nested);
 208 ATF_TC_HEAD(mlock_nested, tc)
 209 {
 210         atf_tc_set_md_var(tc, "descr",
 211             "Test that consecutive mlock(2) calls succeed");
 212 }
 213
 214 ATF_TC_BODY(mlock_nested, tc)
 215 {
 216         const size_t maxiter = 100;
 217         void *buf;
 218
 219         buf = malloc(page);
 220         ATF_REQUIRE(buf != NULL);
 221
 222         for (size_t i = 0; i < maxiter; i++)
 223                 ATF_REQUIRE(mlock(buf, page) == 0);
 224
 225         ATF_REQUIRE(munlock(buf, page) == 0);
 226         free(buf);
 227 }
 228
 229 ATF_TP_ADD_TCS(tp)
 230 {
 231
 232         page = sysconf(_SC_PAGESIZE);
 233         ATF_REQUIRE(page >= 0);
 234
 235         ATF_TP_ADD_TC(tp, mlock_clip);
 236         ATF_TP_ADD_TC(tp, mlock_err);
 237         ATF_TP_ADD_TC(tp, mlock_limits);
 238         ATF_TP_ADD_TC(tp, mlock_mmap);
 239         ATF_TP_ADD_TC(tp, mlock_nested);
 240
 241         return atf_no_error();
 242 }